This adjustable Pet Vest Harness Medium with Breathable Mesh Sublimation is fashionable, strong, lightweight, and composed of Diving Material (Neoprene), Polyester, and Breathable Mesh. The leash can be connected to two D rings on the back to form a harness and a buckle release. Lightweight, soft, and incredibly breathable airflow for a comfortable walking experience. In order to prevent choking of the dog's trachea, we utilize very durable, environmentally friendly material that is designed to distribute the dog's weight evenly across the chest - Neck 15.4"-20"; Chest 18"-24" and can keep your dog warm during winter time.